Installation Manual
3 INSTALL THE REFRIGERANT PIPE
Execute heat insulation work completely on both sides of the 
gas piping and liquid piping. Otherwise, this can sometimes 
result in water leakage.
(When using a heat pump, the temperature of the gas piping can 
O
reach up to approximately 120 /248 F. Use insulation which is 
sufficiently resistant.)
Before rigging tubes, check which type of refrigerant is used.
All field piping must be provided by a licensed refrigeration
technician and must comply with the relevant local and 
national codes.
Use a pipe cutter and flare suitable for used refrigerant.
Do not mix anything other than the specified refrigerant, such 
as air, etc.., Inside the refrigerant circuit.
Coat the flare both inside and ouside with ether oil or ester oil .
If the refrigerant gas leaks during the work, ventilate the area. 
A toxic gas is emitted by the refrigerant gas being exposed to 
a fire.
Make sure there is no refrigerant gas leak. A toxic gas may be 
released by the refrigerant gas leaking indoor and being 
exposed to flames from an area heater, cooking stove, etc.
9
Also, in cases where the temperature and humidity of the
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refrigerant piping sections might exceed 30 /86 F or Rh80%,
reinforce the refrigerant insulation(20mm/0.8in or thicker).
Condensation may form on the surface of the insulating material.
Only use annealed material for flare conncetions.
Coat here with ether oil or ester oil
Precautions
3.1 Flaring the pipe end
1) Cut the pipe end with a pipe cutter.
2) Remove burrs with the cut surface facing downward so that the 
 chips do not enter the pipe.
5) Check that the flaring is properly made.
Refer to the table below for the dimensions of flare nuts spaces 
and the appropriate tightening torque. (Overtightening may 
damage the flare and cause leaks.)
Pipe gauge
 (mm)
Outer diam.
 (mm)
Tightening torque
A(mm)
Max.
1.3
1.6
1.8
2.2
Min.
0.7
1.0
1.0
2.0
Flare dimension
 A (mm)
Flare shape
O6.35(1/4 in)
O6.35(1/4 in)
 15~16 N. m
(153~163 kgf.cm)
 8.3~8.7
0.327~0.343in
 12.0~12.4
0.472~0.488in
 15.4~15.8
0.606~0.622in
 18.6~19.0
0.732~0.748in
 25~26 N. m
(255~265 kgf.cm)
 35~36 N. m
(357~367 kgf.cm)
 45~47 N. m
(459~480 kgf.cm)
O9.52(3/8in)
O9.52(3/8in)
O12.7(1/2in)
O12.7(1/2in)
O15.9(5/8in) 
O15.9(5/8in)
R0.4~0.8
45
2
90
4
A
o
o
1 Torque wrench
2 Flare nut
3 Piping union
4 Spanner 
1 2
3
4
Align the centres of both flares and tighten the flare nuts 3 or 4
turns by hand. Then tighten them fully with the torque wrenches.
3.2 Refrigerant piping
Check whether the height drop between the indoor  unit and 
outdoor unit, and the length of refrigerant pipe meet the following 
requirements:
Capacity
 (Btu/h)
The type of models
Max.allowable 
piping length
15m/49.2ft
25m/82ft
25m/82ft
25m/82ft
9K ~12K
9K ~12K
9K ~12K
9K ~12K
 T1 condition
Split type air conditioner
 R410A inverter
Split type air conditioner
 T3 condition
(outdoor unit down)
 T3 condition
(outdoor unit up)
Max.allowable 
piping height
8m/26.2ft
10m/32.8ft
10m/32.8ft
15m/49.2ft
25m/82ft
30m/98.4ft
30m/98.4ft
30m/98.4ft
18K
18K
18K
18K
15m/49.2ft
20m/65.6ft
15m/49.2ft
20m/65.6ft
Cut exactly at
right angles.
Remove burrs.
Flare's inner surface
must be flaw-free
The pipe end must
be evenly flared in a 
perfect circle.
Make sure that the 
flare nut is fitted.
3) Put the flare nut on the pipe.
4) Flare the pipe.
Die
Copper pipe
A
Set exactly at the position shown below.
(in=mm/25.4)
0.016~0.031in
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